From: Hongtao Liu <crazylht@gmail.com>
To: Jeff Law <jeffreyalaw@gmail.com>
Cc: Hongyu Wang <hongyu.wang@intel.com>,
gcc-patches@gcc.gnu.org, richard.guenther@gmail.com,
ubizjak@gmail.com, hongtao.liu@intel.com
Subject: Re: [PATCH] i386: Only enable small loop unrolling in backend [PR 107602]
Date: Tue, 22 Nov 2022 09:08:17 +0800 [thread overview]
Message-ID: <CAMZc-bymJ=_Csr1Q6cn=pcZm76VhaFf3RMaqucQ4Ep5Eyk-YRQ@mail.gmail.com> (raw)
In-Reply-To: <72ce55ba-2cda-6185-b89a-6d30ea95a383@gmail.com>
On Tue, Nov 22, 2022 at 1:41 AM Jeff Law via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
>
> On 11/18/22 23:25, Hongyu Wang via Gcc-patches wrote:
> > Hi,
> >
> > Followed by the discussion in pr107602, -munroll-only-small-loops
> > Does not turns on/off -funroll-loops, and current check in
> > pass_rtl_unroll_loops::gate would cause -funroll-loops do not take
> > effect. Revert the change about targetm.loop_unroll_adjust and apply
> > the backend option change to strictly follow the rule that
> > -funroll-loops takes full control of loop unrolling, and
> > munroll-only-small-loops just change its behavior to unroll small size
> > loops.
> >
> > Bootstrapped and regtested on x86-64-pc-linux-gnu.
> >
> > Ok for trunk?
> >
> > gcc/ChangeLog:
> >
> > PR target/107602
> > * common/config/i386/i386-common.cc (ix86_optimization_table):
> > Enable loop unroll O2, disable -fweb and -frename-registers
> > by default.
> > * config/i386/i386-options.cc
> > (ix86_override_options_after_change):
> > Disable small loop unroll when funroll-loops enabled, reset
> > cunroll_grow_size when it is not explicitly enabled.
> > (ix86_option_override_internal): Call
> > ix86_override_options_after_change instead of calling
> > ix86_recompute_optlev_based_flags and ix86_default_align
> > separately.
> > * config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll
> > factor if -munroll-only-small-loops enabled.
> > * loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable
> > loop unrolling for -O2-speed.
> > (pass_rtl_unroll_loops::execute): Rmove
> > targetm.loop_unroll_adjust check.
> The reversion of the loop-init.cc changes is fine. The x86 maintainers
> will need to chime in on the rest. Consider installing the loop-init.cc
> reversion immediately as the current state has regressed s390 and
> potentially other targets.
x86 part is ok.
>
>
> jeff
>
--
BR,
Hongtao
next prev parent reply other threads:[~2022-11-22 1:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-19 6:25 Hongyu Wang
2022-11-21 1:01 ` Liu, Hongtao
2022-11-21 1:35 ` Hongtao Liu
2022-11-21 6:12 ` Hongyu Wang
2022-11-21 17:40 ` Jeff Law
2022-11-22 1:08 ` Hongtao Liu [this message]
2022-11-23 1:54 ` Hongyu Wang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAMZc-bymJ=_Csr1Q6cn=pcZm76VhaFf3RMaqucQ4Ep5Eyk-YRQ@mail.gmail.com' \
--to=crazylht@gmail.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=hongtao.liu@intel.com \
--cc=hongyu.wang@intel.com \
--cc=jeffreyalaw@gmail.com \
--cc=richard.guenther@gmail.com \
--cc=ubizjak@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).